The study of personality has adapted and developed over the last several decades and continued evaluation and review of modern theories and models continues to expand current understanding and research into personality and the role it plays in understanding psychology. While there are many different personality theories which attempt to explain personality, two of these theories provide insight through a biological and evolutionary background of personality as well as a focus on the uniqueness and individualism of the individual’s personality. These theories differ from many of the other personality theories which do not address the physiological or biological nature of personality and tend to focus on specific traits which are then attributed across a general population or group. When therapists are providing treatment, they typically provide their treatment to an individual — therefore the individual’s specific personality is much more important to the therapy than a broad swathe of typical or general personality characteristics or traits. In addition to the individual’s uniqueness, knowing their biological background or the general evolutionary background assists in generating a customized therapeutic approach designed for the individual. The theories described are known as dispositional personality theories and evolutionary or biological personality theories.

Dispositional and Evolutionary or Biological Theories

Dispositional personality theories were developed by Gordan Allport and have played a large role in the understanding of personality within the field of psychology (Feist & Feist, 2001). Gordan Allport sought for an additional approach to explain personality and this lead him to his creation of psychology of the individual — an individual oriented approach (Feist & Feist). According to Allport’s definition, personality may be defined as “the dynamic organization within the individual of those psychophysical systems that determine his unique adjustments to his environment” (Feist & Feist). Using this definition, it becomes clear that Allport viewed personality characteristics as being specific to the individual and their environmental circumstances. Based on this, Allport disagrees with the view of general traits across individuals and sees these traits as being different across multiple individuals — multiple individuals may share the trait of stubbornness; however, this trait differs in expression between the individuals and across their unique experiences (Feist & Feist). Due to this, it becomes increasingly important for psychological investigations of an individual to characterize these differences as they pertain to the individual being observed. In contrast to this, the evolutionary/biological theory approaches personality from a more generalized or overall view which attempts to address personality through an evolutionary and biological perspective – viewing personality traits as the product of an individual’s hereditary past. As detailed by Buss (2009), some personality traits contribute to an individual’s ability to survive in their surroundings. Due to those, individuals who display those personality traits are more likely survive and produce offspring who share these genetic differences. In this manner, personality traits can be explained by providing strategic benefits to the individual who display them (Buss). Both of these theories provide a unique insight into personality and provide the field of psychology with differing perspectives which assist in generating a more complete view on personality.

Strengths and Weaknesses

Dispositional personality theories share several specific strengths as well as multiple limitations. Dispositional personality theories have definitely influenced the field of psychology and their strengths have had various impacts as well. Allport’s theory provided psychology with a fresh perspective to delve into personality, a view previously untapped. The dispositional personality theory provides a descriptive and encompassing definition of personality and provides more complete view into what it entails (Fesit & Feist, 2001). In addition to this, the theory has served as a starting point for generating additional research into personality. This theory has also been shown to be internally consistent and parsimonious (Feist & Feist). Some of the key weaknesses behind this theory reside in the methodology used by Allport in his studies. For example, one of the criteria for a strong psychological theory is the use of empirical evidence and research; however, in the case of Allport’s theory, he avoids this empirical approach and favors an approach rooted in philosophy and common-sense — limiting further research as well as the theories falsifiability (Feist & Feist). More importantly, his theory does not accurately address personality research and study into children, individual’s with abnormal psychology, and uncharacteristic or strange individual behaviors (Feist & Feist). In my opinion these limitations also detract from the application of Allport’s theory. While inferences and general principles may be identified from his theory, most practicing therapists focus resides in individuals who fall outside of a healthy or normal personality — areas which Allport’s theory is decidedly lacking. In addition to this, Allport’s theory is also lacking in its falsifiability (Feist & Feist). By nature philosophical approaches lack the empirical evidence and organization necessary to disprove or prove them — thereby falling outside the realm of falsifiability. The evolutionary approach to personality has many differing strengths from dispositional theories. As a theory, evolutionary psychology proves difficult to prove false or not – just as the theory of evolution is controversial in some groups (Feist & Feist). In contrast to this weakness, the evolutionary psychology perspective provides a strong method for organizing knowledge – this assists in the explanation and study of biological systems, human thought, behavior, and personality as well (Feist & Feist). While the theory proves to be strong in organizing knowledge, Feist & Feist identify that the theory is weak in its ability to guide practitioners – while it may show why we are the way we are, the theory does not directly assist in guiding parents in raising their children, how they should be taught, and how to treat mental disorders (Feist & Feist). The theory also has issues with internal consistency – not all individuals agree on what may or may not be classified as an adaptation. The final strength Feist & Feist identify resides in the theory’s parsimonious approach – the theory simplifies many complex concepts. While these strengths and weaknesses provide an overall view of the theories’ limitations and advantages, these primarily address their strengths and weaknesses as a theory and, while they influence how the theories relate to personality, there are additional strengths and weaknesses which reside outside of those identified. In order to address these issues, various additional methods and theories have been generated to provide insight into personality.

The Big Five theory of personality provides additional insight and clarification into personality (Feist & Feist). According to McCrae, Robert, Costa, & Paul (1987), the five factor model (the big five) has passed various assessments and inquiries designed to show the accuracy and validity of the theory – including peer ratings, self-reports, adjective factors, and questionnaire scales as forms of assessment. But what is the five factor model? The five factor model is a theory of personality which emphasizes five dimensions of personality which influence and range across individuals. These include extraversions, neuroticism, openness, agreeableness, and conscientiousness (Feist & Feist). Assessment of these factors allow for the identification and measurement of an individual’s personality – benefiting research and therapy across individuals with varying personalities. This theory is a large step forward in proving and empirical approach which also explains the generalities of personality as well. As the field of psychology advances, additional theories and insight will continue to explain and drive the field of psychology’s understanding of personality.